Coupling means for scaffolding bars



Jan. 22, 1952 R FRENCH 2,583,368

- COUPLING MEANS FOR SCAFFOLDING BARS Filed June 11, 1947 1 4 Sheets-Sheet 1 INVENTOR Merl! i? Wear/v BY g C ATTORNEY M. P. FRENCH COUPLING MEANS FOR SCAF'FOLDING BARS Jan. 22, 1952 4 Sheets-Sheet 2 Filed June 11, 1947 INVENTOR flerle F 77%11/0 ATTO RNEY Jan. 22, 1952 M. F. FRENCH COUPLING MEANS FOR SCAF'FCLDING BARS 4 Sheets-Sheet 3 Filed June 11, 1947 INVENTOR ATTORNEY Jan. 22, 1952 p, FRENCH COUPLING MEANS FOR SCAFFOLDING BARS 7 Filed June 11, l9 47 4 Sheets-Sheet 4 ATTORNEY Patented Jan. 22, 1952 UNITED STATES PATENT OFFICE 2,583,368 COUPLING MEANS FOR SCAFFOLDING BARS Merle P. French, New Rochelle, N. Y.

Application June 11, 1947, Serial No. 753,991

This invention relates to scaffolds, particu larly to metallic type scaffolds employing tubular frame members for supporting material and workmen in building operations, and has for its primary object to provide a quickly erectable scaffold in which the vertical and horizontal frame members are adapted to be interconnected with their axes intersecting each other.

In the erection of rigid scaffolds hinged clamps are usually employed for coupling the vertical and horizontal members together at predetermined points. These clamps are designed to maintain alignment of those horizontal members disposed longitudinally along the exterior of a building with their axes, however, laterally offset from the vertical members to which they are connected, thereby producing a bending moment at each of the joints. It has been proposed heretofore to minimize said bending moment by clamping the horizontal member in contact with its associated vertical member and, while this is an improvement over previous constructions, it is not entirely satisfactory.

It is, therefore, another object of the invention to eliminate the aforesaid bending moment in a tubular frame scaffold.

- Since a scaffold is constituted by a series of front and rear vertical frame members interconnected in depth by horizontal tubular members or ledgers, which are used for supporting flooring planks, it has been necessary heretofore, as far as applicant is aware, to arrange the ledgers at a different elevation from that of the horizontal members that continue longitudinally along the building. This is also an unsatisfactory arrangement, particularly in rolling or stationary tower type scaffolds, and it is still another object of the invention to arrange all horizontal members, including the ledgers, on the same level.

In general, the longitudinal members of a scaffold are continued along a straightaway and where the building follows a straight line this is satisfactory. arcuate or angular lines the straightaway a1"- rangement is not satisfactory since the scaffold length should conform to the contour of the building.

It is thus a further object of the invention to provide universal clamp that is adapted to interconnect the horizontal longitudinal members at any desired angle and also to maintain the transverse members at the same elevation therewith.

able hinged type clamp for tubular type scaffoldsv However, in buildings following 6 Claims. (Cl. 304-40) With the above objects in view, a preferred embodiment of the invention discloses a tubular scaffold in which vertical tubular members are connected to horizontal tubular members both longitudinally and transversely by improved clamps, each of which is provided with a hinge for removable engagement with the vertical tubular member and with an offset projectionfor reception within and fixed attachment to one end of the horizontal tubular member. The center of the projection is ofiset a predetermined amount from the center of the hinge, so that at a juncture involving one vertical and two horizontal members one clamp is disposed with its projection above the hinge center while the other clamp is disposed with its projection below the hinge center line, thereby placing both projections and their associated tubular members at the same level. At the same time the centers or axes of both horizontal members intersect the center or axis of the vertical member. Ledgers disposed adjacent the junctures are provided with clamps havingprojections centered with the hinges and when attached to longitudinal members are .at the same level therewith.

For bracing the scaifold a swivel type clamp comprising a slotted hinge portion pivotally engageable with a tongue portion is rigidly secured to each end of a tubular member of predetermined length and the tubular brace is hingedly connected at one end to a vertical member and at the other end to a horizontalmember. The slotted hinge portion is also adapted. for use with ledgers disposed adjacent the vertical members.

A more complete understanding of the inven-- tion will be obtained'from the following de-.

Fig. 2 is a front elevational view of the scaffold shown in Fig. 1; Fig. 3 is a perspective view of a rolling scaffold tower incorporating the features of this inven tion;

Fig. 4 is a slightly enlarged elevational view, partially in section, of a juncture involving a vertical member and two straightaway horizontal members in which the details of the offset clamp are more clearly illustrated;

Figs. 5 and 6 are sectional views taken along li s 55 and 6,-6, respectively, of Fig. 4;

Fig. '7 is a slightly enlarged sectional view taken along line 'I-I of Fig. 2 illustrating interconnection between a horizontal member and a ledger or transverse member;

Fig. 8 is a view, partially in section, of a juncture involving a vertical member and a bracing member bringing out more clearly the swivel type clamp; and

Fig. 9 is a sectional view taken along lines 9--9 of Fig. 8.

Referring now to the-drawings, particularly to Figs. 1 and 2, there is shown a scaiiold I comprising a plurality of uprights or vertical members I2 connected to longitudinal members L4 and to transverse or ledger members It at one end thereof. Additional transverse .or ledger members I8 are shown connected to the longitudinal members I4 adjacent orintermediate the junctures of the longitudinal and vertical .members I4 and I2 respectively, while bracing members 2.0 are interposed, as desired, between a vertical member I2 and ,arlongitudinal member I4jfor adding rigidityand strength to the scaffold I0. .Allmembers are preferably ,of-tubulardesign in conformity with conventional present day construction.

For quickly attaching one member to another itjis customary to employ hinge type clamps and, as seen in Fig. 2, a clamp 22, termed an offset clamp 'i'orreasons that will appear hereinafter, is secured ,at each endof a longitudinal member I4 andan endledger member 16. By use of the offset clamp 22 it is possible to install the "longitudinal members I4 on a straightaway, thatis, with all members 14 in alignment, or to install these members at various angles with respect to each other in conformity with the outline of a building structure (not shown). At the right side ofFiggl is illustrated an example of a turning pointiin the scaffold I0.

Each end .of an intermediate ledger It is equipped with a straight hinged clamp 24 and each end of abracing member 20-is provided with a swivel type clamp i26,'both of which will be described 'in greater detail hereinafter. It is,

parts is somewhat similar to that shown in Figs. 1 and 2 and it is not deemed necessary, therefore, to go further into the details thereof. However, in cases where the span between uprights I2 is beyond a predetermined length it is considered preferable to install a pair of braces 20 in the form of a truss, as shown, for each tier. To bring out the details more clearly only the braces 20 nearest the observer are shown, it being-understood, of course, that similarly arranged braces would be installed at the opposite side thereof. At the top of the tower 28 there is 'shown a railing 32 comprising the longitudinal I vand end ledger members I I and I6, respectively,

1 therefore, readily apparent fromFig. 1 that the centerlines or axes of the longitudinal members I4 and endgledgers I6 intersect the center lines or axes of the vertical members I2 at their junction points. Thus, the weight of material, workmen,-etc. '(notshown) carried by the horizontal members .14, I6;and I8 is transmitted vertically to 1theuprights I2 without any lateral bending moment, as is found in existing scaffolds. Itis to be noted, iurther, that'the-axes ofthe bracing members 20 also intersect the axesof the vertical and horizontal members I2 and I4, respectively, thereby eliminating bending moments and side thrusts at 'iunctures therewith.

It is advantageous in scaffolding structures'to locate all "ledgersandlongitudinal members at the-same level or elevation in order to facilitate theinstallation of-planks (not-shown) as a-flooring for supporting material'and workmen. As

, shownin Fig. 2, theend and intermediate lodgers connected to free ends of the uprights I2 as a safeguard for the workmen.

InFigs. 4-5,and 6 details of the offset clamp 22 and its coupling arrangement between the longitudinal members I4 and vertical member I2 are shown. The clamp, in general, comprises a mainibodyrportion 34 having an arcuate con caverecess ,36, complementary to the peripherai surface .pf-the vertical member I2, and an arouate hinged plate38 for embracin-gly engaging the member 12. A bolt 40 is rotatably pinned at one end inrthe body 34, as shown, and its shank 42 is adapted to be received in a slot 44 provided at a bifurcated end portion 46 of the hinged plate '38. A nut 48, which is threadedly engage able -with-the bolt '48, is adapted to bear'against the face of the bifurcation 4a in the closed position of :the clamp 22. For limiting the extent to which the hinged plate 38 may be opened, a protuberanceor stop so is provided, as shown.

Ashanki52 extends outwardly from the body 34 andat its extremity there is formed a lug 54 with a projection 56,-which is preferably circular and of a size slightly smaller than the inner diameter of the longitudinal member I4 or ledger I6, within which it is adapted to be received and attached thereto in any suitable manner, as'by' a'bolt-nut combination 58. As shown clearly in Fig. 4, the center line or axis of the projection 56 coincides with that of the tubular member I 4 and this center line also coincides with the upper edge 60, as viewedin Fig. 4, of the main body 34 of the lower clamp 22. Further, the center line of the projection .56 is offset or spaced from the centerline of the main body 34 a predetermined amount, .whichamount is shown as being onehalf the height of the body 34. Thus With this amount of offset it is readily seen that by re versing-the-positions of the projections 56 with the ,clampedges 60 in abutting engagement, as illustratedin Fig. 4, the center lines of the longitudinal membersare inalignment and, therefore, theyouterperipheral surfaces thereof are at the same elevation. And this same elevation will be i obtained-regardless of the angle between the two members. which in Fig. 5 is shown to be at that is, ona straightaway. This angle ma?) be.90?,.as at the'end of a scafiold (see left end of Fig. "1 andends of Fig. 3), or at an acute or obtusea-ngle (,see'right end of Fig. 1.).

It will also'be readily seen in Fig. 5 that the center lines of the horizontal members I4 inter-- sectthe'centerline of the vertical member I2 and'in view of this intersection any load carried by the horizontal members I4 will be transferred directlyto the upright I2 by the vertical force component, the horizontal force component being zero. 'Inrpresent scaffolds employing hinge type W clam-pans fanasapplicant is aware, the'horizontal members-.are.riisposed at the side of the upright with a resulting force bending moment or torque existent at the juncture. V Referring now to Fig. 7, there is shown the ledger l8 provided at its extremity with the clamp 24, which differs from the clamp 22 merely by a change in the location of the projection. In the clamp 24 a projection 62 is formed along the axis or center line of the body 34 and this projection is disposed within the ledger l8 and secured thereto by bolt-nut combination 58, thus providing what may be termed a straightaway clamp. It is apparent, therefore, that the ledgers 18 are at the same elevation as that of the longitudinal members [4 and end ledgers It.

The swivel clamps 26, shown in Figs. 8 and 9 are formed of a male and a female part, the male part comprising a cylindrical member 64, preferably solid, disposed within the tubular brace 20. being secured thereto by a nut-bolt arrangement 66, and a flat tongue member 68 extending from the cylindrical member 64. The tongue 68 is formed with a transverse opening 10, a shown. The female part includes a straightaway projection 12 with a bifurcated end [4 having a slot 16 for reception therein of the tongue 58, the remainder thereof being substantially identical to that shown in Fig. 7. In fact, to reduce the number of parts, clamp 24 and the female portion of clamp 26 may be identical. The bifurcated end 14 is formed with a transverse opening 18, which registers with the opening "1 when the tongue 68 is properly disposed in the slot 16 of the projection 12. A pin or rivet 80 passed through said openings forms a pivot as shown for the tongue 68, which may be rotated with the brace member 20 to any desired angle. From inspection of Fig. 9 it can be seen that the axis of the brace 20 intersects that of the upright I2, so that the load will be transmitted from one to the other along axial lines. While in Figs. 8 and 9 the upright l2 Was shown coupled to the brace 20, it is to be understood that the longitudinal member l4 could be substituted for the upright I2 with the same result.

The method of assembling the scaffold ID will now be described. An upright i2 at one end, say the left rear end of Figs. 1 and 2, is first set up. A longitudinal member 14 of the desired length having a clamp 22 at each end is next clamped at the required height to the upright l2, a right angle being automatically formed at the juncture. As shown in Fig. 2, the offset projection 56 of the clamp 22 is in the upper position, although it could be in the lower position. A seeondupright I2 is then placed in the recess 36 of clamp 22 while in the open position and the hinge 38 locked into closed position, a right angle being automatically formed at this second juncture. If

a building structure is adjacent the proposed scaffold H), the three assembled parts are usually inclined thereagainst (otherwise these parts are held vertically). The left end ledger I6 is next connected to the first installed upright l2 with clamp 22 thereof placed above and in abutting engagement with the first installed clamp 22, the offset projection 56 of the ledger l6 extending downwardly and, therefore oppositely to that of the latter clamp 22.

The left front upright i2 is then set plumb at the required spacing from the associated left rear upright l2, after which the two. rear uprights I2 are brought to a vertical position and the remaining clamp 22 of the ledger l6 coupled to the left front upright l 2. The three uprights are self-sustaining at this point and the left front longitudinal member-ll is then connected to the left front upright l2 with its clamp 22 in abutting engagementbeneath the clamp 22 of the ledger IS, the offset projection 56 of member It being directedjipwardly. The fourth upright 12 is coupled to the free end of its associated longitudinal member l4, after which braces 20 are clamped into position, as shown at the front and back, and an intermediate ledger it connected between the two longitudinal members M. In a similar manner the remainder of the tier or level, as well as the required number of upper tiers, is installed until the entire struc' ture is completed.

While this invention has been shown and described as embodying certain features merely for the purpose of illustration, it is, of course, understood that various modifications may be made in the details thereof without departing from the scope of the invention, asgdefined in the appended claims.

What I claim is:

1. A scaffold comprising, in combination, a vertical tubular member, a pair of horizontal tubular members connected thereto, and a hinge clamp with an offset portion of one-half the height of the clamp telescopically secured to each of said horizontal members for connecting 'said horizontal members to said vertical memher, said portions being vertically offset on said vertical member in opposite directions to maintain said horizontal members at the same elevation, said clamps being adapted to interconnect said members so that the axes thereof intersect each other.

2. A scaffold comprising, in combination, at least a vertical member, a pair of horizontal members adapted to be connected thereto with the three axes thereof intersecting each other, said horizontal members including a clamping device rigidly attached to each end thereof, said device comprising an oiiset portion equal to one half of the height of said clamp with an arcuate rotatable hinged plate for frictional engagement with said vertical member, said portions being vertically offset on said vertical member in opposite directions, so that one offset portion balances the other offset portion, thereby maintaining said horizontal members at the same elevation.

3. In a scaffold, the combination with a vertical tubular member and a pair of horizontal tubular members connected at a junction point thereto, of a clamp rigidly secured to an end of each of said horizontal members, said clamp comprising a body vertically offset one-half the height of said clamp from the axis of said horizontal member, and a hinged plate rotatably carried by said body for embracingly engaging said vertical member, said clamp being disposed on said vertical member at said junction point in abutting relation with the bodies ofiset in opposite directions.

4. In a scaflold, the combination with a vertical tubular member and a pair of horizontal tubular members connected at a junction point thereto, of a clamp rigidly secured to one end of each of said horizontal members, said clamp com prising a body vertically offset one-half the height of said clamp from the axis of said horizontal member, one edge of said body being in alignment with the axis of said associated horizontal memher, and an arcuate hinged plate rotatably-carried by said body for embracingly engaging said vertical member, said clamp being disposed on said vertical membe at said junction hoi nt i'n abutting relation with" the bodies offset in opposite' directions; v I

5. A coupling for-a pair of tubular: members comprising, in combination,- a body, an arcu ate hinged plate,rotatably'carried upon one side of said body for removabl'ysecuring one of said members to said body, a'shank extending outwardly from another side of said body, a lug extending transversely from said shank, and a projection extending transversely from said lug and parallel with said shank for rigid attachment to the other one of said tubular members, said projection having its center line disposed transversel'y' from the" center line of said body one-half the height of said body and said projection being adapted for telescopic attachmerit to the other" oneof said tubular members.

-6. A'coupli'ng' for securing a horizontal'tubular member to a vertical tubular membercomprising, in combination, a body,-a-n a rcuatehi'nged plate rotatably carried upon oneside of said body-for removably securing said vertical member to said body, a shank' extending horizontally from another side'ofsaid body, a lug extending vertically from-said-slianlg, a projection extending horizontaliy'fromsaid-lug for rigid attach- MERLE P. FRENC I-I REFERENCES CITED 7 The, following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 611,588 Brooks Sept. 27, 1898 1,197,487 Hinds et a1 Sept. 5, 1916 1,416,386 Selah May 16, 1922 1,527,400 Frankel Feb. 24, 1925 1,770,852 Hill July 15, 1930 1,828,487 Booser Oct. 20, 1931 2,113,196 Jones Apr. 5, 1938 2,267,323 Chilcott et a1 Dec. 23, 194i F RE G A' IE S Number Country Date 308,873 Great Britain Apr. 4, 1929 491,162 Great Britain Aug. 29, I938 

